⚡ Electricity

1. An electric circuit is made up of different parts that are connected together to allow current to flow through it.
2. The different parts of an electric circuit are known as electrical components and have their own functions.
3. A simple electric circuit consists of a battery, some wires, a bulb and a switch.

Electrical Component	Function
Wire	Connects electrical components to one another
Battery	Energy source
Light Bulb	A light source
Switch	Controls the flow of electric current

4. A battery is the energy source of an electric circuit.
5. It has a positive (+ve) terminal and a negative (-ve) terminal.
6. When the positive terminal is connected to the negative terminal, the chemicals in the battery react to produce energy.

7. A wire is made of a thin strand of metal.
8. The most common metal that is used to make wires is copper.
9. Wires are used to connect electrical components to one another to allow electric current to flow.
10. Wires are usually insulated with a plastic/rubber covering.

11. A bulb is a light source.
12. A bulb produces light and heat when electric current flows through it.
13. A bulb is made up of different materials such as metal and glass.
14. A bulb consists of a metal filament, a glass bulb, a metal casing and a metal tip.
15. The metal tip and metal casing must be properly connected to an electric circuit to light up a bulb.

16. A switch controls the flow of electric current in an electric circuit.
17. If the switch is closed, electric current will flow.
18. If the switch is opened, no electric current will flow.

Closed Circuits

1. A closed circuit is formed when all the electrical components in an electric circuit are connected without any gaps.
2. An electric current only flows in a closed circuit.
3. Electric current flows through and lights up the bulbs in a closed circuit.

Open Circuits

4. An open circuit is formed when there is a gap between the electrical components in an electric circuit.
5. No electric current flows in an open circuit.
6. Electric current does not flow through and light up the bulbs in an open circuit.

1. Electrical conductors are materials that allow electric current to flow through them easily.
2. Metals such as steel, copper and aluminium are electrical conductors.
3. Some non-metals such as graphite that pencil "lead" is made of are also electrical conductors.
4. Electrical insulators are materials that do not allow electric current to flow through them.
5. Non-metals such as wood, glass, plastic and rubber are electrical insulators.

Type	Definition	Examples
Conductors	Allow electric current to flow through them easily	Metal (steel, copper, aluminium), graphite (pencil lead)
Insulators	Do not allow electric current to flow through them	Non-metals (wood, glass, plastic, rubber)

Circuit A — Iron Rod (Conductor)

6. The bulb in Circuit A lit up.
7. The iron rod is a conductor of electricity and a closed circuit is formed.
8. Hence, current flowed through the bulb, causing the bulb to light up.

Circuit B — Glass Rod (Insulator)

9. The bulb in Circuit B did not light up.
10. The glass rod is a non-conductor of electricity and an open circuit is formed.
11. Hence, no current flowed through the bulb, causing the bulb not to light up.

12. To test whether an object is an electrical conductor or an electrical insulator, we can use a simple electric circuit.
13. The object is placed between the two crocodile clips and the switch is closed.
14. If the bulb lights up, the object is an electrical conductor.
15. If the bulb does not light up, the object is an electrical insulator.